At least for the last one hundred years, a common problem in the mop industry has been to manufacture mops, whether they be wet mops, dry mops or dusters, so that the mops withstand extended usage and do not excessively fray or lint off. For many years mops were generally either wet mops or the so-called oil mop. The latter was usually a triangular arrangement with either looped or cut end yarns and which was soaked in oil to better attract dust and impart a sheen to the surface of a wood floor. The wet mops were used for the heavier mopping tasks and had to withstand loading with soapy water and scrubbing at soiled areas on the floor. The predominate enemy of both these types of mops was moisture, whether the moisture be in the form of water or oil, because the moisture tended to fill the intersticial openings in the mop yarns, thereby causing separation of the fibers, and generally made the mop yarn heavier, causing the fibers to tend to separate longitudinally. The result was linting during use, which left unsightly streaks upon the finished floor, and accumulation of lint balls that collected under furniture and provided breeding places for alergen producing molds, mites and fungi.
With the 1950's and the decline of the oil finished wood floor came the rise of dry mops, or the typical elongate, flat janitor's mop now in common use on the terrazzo, tile or otherwise hard finished floor of commercial establishments, gymnasiums and the like. The janitor's mop needed washing after each use to remove the accumulated dust and dirt and this spurred the growth of the mop rental industry. Under a typical arrangement, a rental agency would buy mops from a manufacturer and would provide a clean, fresh mop to janitorial service businesses at the start of each night's clean up. Because the mop was frequently washed, it became imperative that the mop be able to withstand the cleaning process without the mop yarns unraveling and turning to a linty, fibrous mass during washing. Because the rental business purchased the mops from the manufacturer and distributed them nightly, the inducement was clear to provide a mop which could withstand sufficient washings to recoup the initial purchase investment and to provide a reasonable profit to the rental business, as well as being a product that the janitorial service would accept as an effective mopping tool.
As a result of the effort to construct a mop able to withstand repeated washings and still provide effective cleaning capability, several approaches were taken. One course was to make the mop yarns of a synthetic material. Previously, mop yarns had been all cotton, which was favored for low cost, ability to hold water or oil and its ability to attract and pick up dust. Cotton fibers were generally not very durable and various synthetics, such as saran, nylon, rayon and the like were introduced in varying proportions with the cotton fibers to form the yarns. The difficulty with the synthetic fibers is that generally the synthetic fibers do not provide the water absorbency and dust gathering qualities of the all cotton yarns and are often harsh to feel, signaling to the perspective purchaser that, while the mop might better withstand repeated washings, its effectiveness as a cleaning tool might be degraded.
Another avenue of approach came in the recognition that cut ends of the mop yarns were the places that permitted the yarn to untwist, bloom and lint off. That recognition led to the expansion of the use of looped end yarns, which had begun at least as early as the 1880's. These looped ends kept the mop yarns intact longer by retaining the yarn twist and did not provide the bloomed cut ends which often readily shed lint.
Rug and mop manufacturers have attempted to alleviate the problems associated with the use of cut end yarns by a tufting process in which a yarn pile is formed by needles which penetrate a backing. However, tufting machinery is expensive, and the tufting process is more suited to large run activities where wide expanses of yard goods must be covered with yarn pile, such as in rugs or carpeting, rather than short and small run, often odd shaped mops.
Mops have often been made by a pre-sewn fringe technique. One such machine for making pre-sewn fringe is disclosed in the Feighery et al. U.S. Pat. No. 3,299,844. Such machines usually include a winding arm which revolves about yarn carriers that are generally in the form of spaced, parallel bars about which chains travel. The winding arm wraps the yarn about the yarn carriers and the chains move the wrapped links of yarn toward the exit of the machine. A sewing head is situated between the arms and stitches the wrapped yarn so that it comes off the machine in long lengths of pre-sewn fringe. This fringe is then used in individual strips, or coiled concentrically onto backings to form various types of mops, whether it be hand mops, dry mops or buffing pads.
The instant invention involves a particular construction of mop and a process for making pre-sewn yarn, and ultimately mops, using a particular formation of yarn and in treating such yarn so that the yarn forms closed, looped ends and which yarn resists linting and is highly durable in use.